Development of solar cells has been being made energetically in view of various aspects aiming at the improvement in light energy conversion efficiency, durability, operation stability, production easiness, or reduction of production cost. Particularly, since semiconductor layers, which can be said the heart part of solar cells, influence on the light energy conversion efficiency greatly, their materials and structures have been eagerly studied. For example, as materials for composing semiconductor layers, research and development have been made on materials such as IV group semiconductors, compound semiconductors, organic semiconductors, and oxide semiconductors, some of which have already been in practical use. However, the light energy conversion efficiency of conventional solar cells is still not satisfactory, solar cells having a higher light energy conversion efficiency have been in great demand.
The first object of the present invention is to provide a semiconductor layer used in solar cells having an excellent light energy conversion efficiency.
The second object of the present invention is to provide a method for producing the above semiconductor layer.
The third object of the present invention is to provide a solar cell having an excellent light energy conversion efficiency using the above semiconductor layer.
The fourth object of the present invention is to provide a method for producing the above solar cell.
The fifth object of the present invention is to provide uses of the above solar cell.